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Composing shapes

Sal combines shapes to make other shapes.

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Video transcript

Use these semicircles, a semicircle semi means half So use these half circles to make a circle so if you take two halfs of a circle and if you put them together just right You're going to make a circle So how do we do that? Well this first choice right over here, these are no longer the semicircles These are each a third of a circle So we're not gonna, and this isn't even complete the entire circle so that didn't make a circle This one, they took the two semicircles but they didn't make them so that their outsides completely line up with each other. so this isn't a circle But this one they took the two semicircles and they put them together just right so now their outsides line up and we have a full circle So that's our choice and we got it right Let's keep doing this Use these small triangles to make a big triangle All right, well here, they used them to make not a triangle but this looks like a parallelogram, a quadrilateral Here, they've used the two triangles and made a triangle because this whole thing has three sides one, two, three Here they used those two triangles to make a square but we wanna make a big triangle so this is our choice Let's do a few more of these Use these semicircles to make a circle Well here, they're not meeting on the flat side so this isn't a circle This looks like something else like two smiles or something Two pieces of a blue watermelon which is sliced on top of a purple one This is a circle So that, they put the two semicircles in the right way Here they didn't even make the meet so this would be our choice Use these small rectangles to make a big rectangle Well here they didn't line them up right to make a big rectangle Here they did This whole thing has one, two, three, four sides so I'll click that one This one doesn't look like a rectangle It looks like some type of an L or something So I'm not going to select that one We got it right